CARB HELP PLEASE.

[gsxr400 91]

Here We have another Carb related fault and Any HELP would be most appricated. Followed the Tony Sleep Carb thingy.... also other ppls advice and experience.

Right first up work already done:
All the O Rings Replaced from polymax.co.uk
Striped cleaned and checked. Everything is stright clean no blockages etc
Floats hights checked, all fine
x2 small repair to the to the main jet , Been heli coiled ( by some one else whom stripped the thread?) and a replaced Nut to the slide holder.

No leaks and everything connected up correctly ... i think both fuel hoses connected up and the oil breather + vacuum pipe. also the x2 that go to the air box. Fuel tap set to Prime.... (and tried the open position also)

AND .... (Drum roll)..... The F ing thing wont start!!!

The plugs aint getting wet.... no fuel getting there??? i dunno but
Spark present...
Compression ... Fine
Battery Fully charged and turning over perfectly
Fuel tap working as it should.

Tried everything that i can think of.. they've been on + Off more time i care to mention and cant figure out why it wont start.

(Just to mention also, the bike was running before the carb build just very poor.)

Someone suggested easy start to get it to fire then hope the engine takes over ... pulling the fuel through.??

Help please, really would like to get this running over the bank holiday weekend.

Cheers

[gsxr400 91]

also forgot to mention . apparently has been stood sice 2005 untill last month. was running poorly for a few weeks.... this is when i aquired it followed by the carb rebuild.

[Variablevalves suck]

If it ran before you stripped the carbs its most likely these that are causing the problem.
Did you do any other work?
I would be looking at the pilot system, have you refitted the pilot screws correctly?

[gsxr400 91]

Only other work been done are the cables throttle choke and clutch. Rear sub frame change and other costmetic work.

Pilot system ... Errmm i believe so every thing were nipped up tight. As for the pilot screw again these were nipped up then backed off x1.5 - x1.8 tried both but no joy. I know they are aint blocked tho.

?????

[Marsbar]

Tried bumping it? when I rebuild my bike it wouldn't start of the button for poop. then I tried bumping it (in 3rd gear) it started right away. Then rand for 30 seconds, now starts of button every time. Strange i know but worked for me :/

[xXxKillDogxXx]

When i fitted my carbs for the first time i ended up draining my battery trying to start it from the button u really have just gotta keep going if anything keep it stuck on prime and keep on trying to make it fire

[gsxr400 91]

I tried it over n over. Guess ill try more. And will also try a bump start.
Some one suggested using easy start to to see if it will fire...they went on to say the engine might just take over similar to marsbar's bump start.

Brought a compression tester to get a more accurate reading to see whats going on in all 4 cyclinders.

But if it not getting any fuel to the plugs is that because theres no vacuum? Thought the vacuum were made vy the compressions made by the piston. This is were it gets a little more technical for me cause im not sure

Any other suggestions what to try or look for or any other suggestions ????

[rgvsp]

I'd try running the bike with a different fuel source than the tank so you can 100% eliminate the petcock and then concentrate on the carbs. If it starts then it is the petcock. If not, you keep looking at the carbs.

[dobbslc]

GSXR's seem to be very tricky sometimes, the fuel tap can be a pain in the arse so check it with a seperate small tank first, you can by them on ebay for about £25 it will be one of those tools that you wished you bought years ago!
Try a bit of easy start as that can help get things flowing.
If as you said the bike was sitting for years it my have blocked some of the tiny carb body drillings that can't be reached, ultrasonic cleaning is the only way to go here, I bought a cleaner a while ago and you won't belive the shit that comes off even a clean set of carb's, It worked really well on my totally shagged fzr carbs then a set on my gsxr. I'll clean them for you if you live nearby.

Dobbs

[gsxr400 91]

Will check the fuel tap... Seem ok when i stripped it the diaphram were fine and seemed to move freely.
Just out of interest are the fuel taps same as the 600 +750 etc cause u can by replacements taps and rebuild kits and they look identical????

Think ill start with an easy start method . Cant hurt to try and who knows could be something so simple as this.

Ultrasonic cleaning ummmm sound like a thought if all else fails but live no where near you. But thanks. . . Got few parts on order new float bowl and jet holder gaskets n that... Replaced everything else.

Cheers for all the responces though. Gave ne bits to look at